Man who shot four NY firefighters was convicted for killing grandmother

William Spengler, the man who authorities say shot at volunteer firefighters responding to a call in Webster, New York Monday morning, was convicted of killing his grandmother in 1980.

Four firefighters were shot Monday. Two were killed and two were taken to the hospital for injuries. Joseph Hofstetter and Theodore Scardino are still at a hospital in Rochester recovering, reports USA Today.

Webster Police Chief Gerald Pickering told the media that it appeared that it was a “trap,” which prevented the volunteer firefighters from responding to the call. Police now know more about what happened, revealing that Spengler is believed to have set the house he and his sister lived in ablaze, then waited for the firefighters to arrive.

According to CNN Spengler, 62, spent nearly 18 years in prison for killing his grandmother in 1980. He was released in 1998 and, as a convicted felon, he could not legally own firearms. Officials do not know how he obtained the weapons.

“Just looking at the history, obviously this is an individual who had a lot of problems, to kill his grandmother,” Webster Police Chief Gerald Pickering said. “And I'm sure there were ... mental health issues involved.”

CNN also reported that Spengler left a three-page note with his intent to kill. "I still have to get ready to see how much of the neighborhood I can burn down and do what I like doing best -- killing people," police say he wrote.

Spengler's sister, 67-year-old Cheryl, is still unaccounted for.

The firefighters who died were Webster Police Lt. Michael Chiapperini, 43, and Tomasz Kaczowka, 19. Kaczowka was also a 911 dispatcher.